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DFT calculations were performed on (S)-methyl tetrahydrofuran-2-carboxylate to facilitate the interpretation of IR and VCD spectra. The potential energy surface could not be described unambiguously using the 6-31G* basis set in combination with different density functionals including B1LYP, B3LYP, B3P86, B3PW91, B98, BHandH, BHandHLYP, MPW1PW91 and PBE1PBE. In contrast, a uniform conformational picture could be found using the cc-pVTZ basis set. Using this large basis set and the collection of nine functionals from above, the dipole and rotational strengths were calculated, and compared to experimental values which were extracted from the experimental IR and VCD spectra for (+)-(S)-methyl tetrahydrofuran-2-carboxylate. A detailed analysis on the agreement between experiment and simulated spectra was performed by assigning the experimental bands based on the harmonic fundamentals obtained for all functionals except BHandH, which performs badly over the whole line. Assessing the dipole strengths, all tested functionals perform equally well. For the rotational strengths, differences can be observed: B3LYP, B1LYP and B98 give the highest correlation with experiment, while PBE1PBE gives the lowest correlation. Comparable conclusions are obtained using a neighborhood similarity measure.

Different high-performance liquid chromatographic methods were developed for the separation and identification of enantiomers of diendo- and diexo-3-aminobicyclo[2.2.1]heptane-2-methanol and diendo- and diexo-3-amino-bicyclo[2.2.1]hept-5-ene-2-methanol derivatives. Direct separation was carried out on a naphthylethyl carbamate-derivatized beta-cyclodextrin (Cyclobond I 2000 SN) stationary phase, which was used in the polar-organic mode. This allowed the simultaneous separation of stereoisomers of alcohol and ester analogs of the bicyclic 1,3-amino alcohols. Alternatively, the derivatization of amino alcohols on the amino group with 1-fluoro-2,4-dinitrophenyl-5-L-alanine amide produced diastereomers which were separable with high resolution (Rs>5-10) on a LiChrospher RP-18 stationary phase. The order of elution of the enantiomers was determined by both direct and indirect methods.

In this study, 6-methyl-2'-deoxyuridine, an artificial nucleoside, was labeled with 11C in the methyl position. Tissue distribution of 6-methyl[11C]-2'-deoxyuridine was investigated in normal Wistar rats and compared to the behavior of the natural nucleoside [methyl-11C]thymidine. High renal clearance, up to at least 20% of the injected activity, was noticed during the 20 min period following injection. Tissue distribution as determined by dynamic PET studies of both 11C-labeled nucleosides was significantly different for most of the organs.